Parents ask why we use fins in the upper levels so often. We find that fins are a marvelous teaching tool. Most people's definition of swimming is not drowning. While we talk to the student about technical aspects of their stroke all the student is thinking is that they are in deep water and I want to make it to the wall. The use of fins takes all of the trepidation away and allows the student to think about the coach's instruction. It also makes it easier to do complex stroke drills that are used to teach stroke mechanics. These drills are used on Thunder and it allows the kids to have a successful first attempt at mastering a difficult task.
Fins also help improve the swimmers kick. They have to kick straight legged and it increases the ankle flexibility, one of the keys to a strong kick. Some kids have a tendency to lock their ankle, almost like they have a boot one their foot. The fin forces the child to have a larger range of motion in a good swimming technique. It really improves the strength of the legs and allows them to become strong kickers, one of the checkmarks for a successful competitive career.
Finally, fins are fun. It is great to be jet propelled in the water. It builds confidence and when we start to reduce the amount of fin time the swimmers make a transition to a successful competitive athlete.